Finding a method to use refinery or other petroleum based wastes is a considerable problem. Currently available processes can be costly, time consuming and inefficient. A number of processes to do this have been described in the prior art.
U.S. Pat. No. 4,990,237 discloses a method for oil recovery from waste oil sludge by centrifugation, volatilisation, condensation and separation by settling.
U.S. Pat. No. 4,897,205 covers the treatment of petroleum sludge by use of steam and a re-circulating solvent to decrease viscosity followed by separation of the solid and liquid components by settlement. Further examples are provided in WO 02/10293.
Asphaltenes are constituents of crude oils. They contain a multiplicity of structures, especially high molecular weight, fused aromatic components and may contain heteroatoms such as O, N or and/or S. As they are very complex, asphaltenes are generally defined in terms of solubility, e.g. soluble in benzene but not in n-pentane.
Asphaltenes can precipitate and be potentially problematical during production, refining, transport and storage of crude oil and products derived from crude oil, for example heavy fuel oil, residual fuel oil, Bunker C or marine fuel.
Depending on the final use of the oil problems can occur due to precipitation of asphaltenes in valves and pipes and on hot surfaces such as heat exchangers. In ships precipitation of asphaltenes can lead to poor combustion, handling and storage problems.
To reduce the viscosity of heavy and residual fuel oils dilution with solvent is sometimes used. Here too handling and storage of the oils can be disrupted by asphaltene precipitation.
Asphaltene dispersants for use in the above applications are already known. For example CA 2029465 and CA2075749 describe alkylphenol-formaldehyde resins in combination with hydrophilic-lipophilic vinyl polymers.
The present invention alleviates the problems of the prior art.
In one aspect the present invention provides a process for the treatment of crude oil or aged crude oil residue comprising the steps of (a) contacting the oil or residue with a phenol resin and with a diluent, to provide a diluted phenol resin treated oil or residue; and (b) optionally removing solid material from the diluted phenol resin treated oil or residue.
In one aspect the present invention provides a treated crude oil or treated aged crude oil residue prepared by a process as defined herein.
In one aspect the present invention provides a residual fuel oil, boiler fuel, marine fuel, Bunker C, blending components for bunker fuel or bitumen comprising a treated crude oil or a treated aged crude oil residue prepared by a process as defined herein.
In one aspect the present invention provides use of a phenol resin for increasing the stability of a crude oil or an aged crude oil residue.
Further aspects of the invention are defined in the appended claims.
Surprisingly in an application to recover residual fuel oil from crude oil or aged crude oil residue (residual pitch) it has been found that the use of additives during the process makes it possible to dilute the crude oil or aged crude oil residue with lighter components that would otherwise have caused flocculation of asphaltenes. The inclusion of additives enables the production of saleable stable heavy fuel oil blends from these types of material.
It is understood that the phenol resin improves the stability reserve of the oil or residue compatibility and/or the compatibility between asphaltenes and the oil or residue. In particular it is believed that the addition of the phenol resin as require by the present invention may increase the compatibility of the “heavy fuel oil” components of the residue with other components such as the diluent. Consequently on addition of the diluent to the residue no problems are observed. In contrast stability problems were observed when the residue without additives was blended with diluent, such as a lighter feed stock.
Crude Oil
It will be understood that by the term “crude oil” it is meant unrefined crude oil. That is crude oil containing all fractions thereof.
In one aspect the crude oil is heavy crude oil. Heavy crude oil is understood to mean crude oil having an API gravity of less than 28 degrees.
API gravity is the gravity or density of liquid petroleum products devised jointly by the American Petroleum Institute and the National Bureau of Standards. The measuring scale is calibrated in terms of degrees API. The formula for determining API Gravity is as follows:Degrees API Gravity=(141.5/Specific Gravity at 60° F.)−131.5
Thus in a further aspect the present invention provides a process for the treatment of heavy crude oil or aged crude oil residue comprising the steps of (a) contacting the heavy crude oil or residue with a phenol resin and with a diluent, to provide a diluted phenol resin treated heavy crude oil or residue; and (b) optionally removing solid material from the diluted phenol resin treated heavy crude oil or residue.
Aged Crude Oil Residue
The aged crude oil residues may be any residual component from crude oil refining which have been aged by subsequent storage in the presence of air.
A typical residual component is atmospheric residue, the residual component from crude distillation, which has a boiling range starting from around 350° C.
Components from other processes such as visbreaking, thermal cracking or catalytic cracking that are in this boiling range, or above, may also be considered.
In a preferred aspect the crude oil residues are from thermal cracking or atmospheric distillation that has been undertaken with processing conditions that have promoted cracking to increase gasoline and distillate production but have produced a residual component of higher density, higher aromatics and asphaltene content, and containing increased levels of coke.
The crude oil residue described herein, although normally useable in fuel oil blending or as feedstocks for other processes, have been rendered unusable by a combination of actual refinery processing originally undertaken and subsequent storage conditions. This may result in a high density, high boiling point material with up to/over 30% of associated asphaltene, carbon particles and other solid (sand etc). As such the residue is not directly usable as a fuel oil or fuel oil component because of the difficulties associated with handling, storage and distribution, combustion and blending.
In another aspect the crude oil residue may be materials that have accumulated as residues in tanks during distribution and storage of crude oil or heavy fuel oil products. An example is the sludge found in the bottom of marine fuel tanks.
The crude oil residue may be aged for a period from production such that it has been rendered unusable in fuel oil blending or as a feedstock
For example, the crude oil residue may be aged for a period of up to 1 year from production, or for a period of up to 1 month from production, or for a period of at least 1 month from production, or for a period of at least 1 year from production, or for a period of at least 2 years from production, or for a period of at least 3 years from production, or for a period of at least 5 years from production, or for a period of at least 10 years from production, or for a period of at least 20 years from production or for a period of at least 50 years from production.
Process
As discussed herein in a broad aspect the present invention provides a process for the treatment of crude oil or aged crude oil residue comprising the steps of (a) contacting the oil or residue with a phenol resin and with a diluent, to provide a diluted phenol resin treated oil or residue; and (b) optionally removing solid material from the diluted phenol resin treated oil or residue.
In one aspect an aged crude oil residue is treated. Thus there is provided a process for the treatment of aged crude oil residue comprising the steps of (a) contacting the residue with a phenol resin and with a diluent, to provide a diluted phenol resin treated residue; and (b) optionally removing solid material from the diluted phenol resin treated residue.
In one aspect crude oil is treated. Thus there is provided a process for the treatment of crude oil comprising the steps of (a) contacting the oil with a phenol resin and with a diluent, to provide a diluted phenol resin treated oil; and (b) optionally removing solid material from the diluted phenol resin treated oil.
The phenol resin may be added to the oil or residue before addition of the diluent, after addition with the diluent, together with the diluent or combinations thereof. If the phenol resin and the diluent are contacted with the oil or residue simultaneously, the phenol resin and the diluent may be contacted separately, in combination or both.
In one preferred aspect the present invention provides a process comprising the steps of
(a) contacting the oil or residue with the phenol resin to provide a phenol resin treated oil or residue
(b) combining the phenol resin treated oil or residue with the diluent to provide a diluted phenol resin treated oil or residue; and
(c) optionally removing solid material from the diluted phenol resin treated oil or residue.
In one preferred aspect the present invention provides a process comprising the steps of
(a) combining the phenol resin and diluent
(b) contacting the combined phenol resin and diluent with the oil or residue to provide a diluted phenol resin treated oil or residue, and
(c) optionally removing solid material from the diluted phenol resin treated oil or residue.
In one preferred aspect the present invention provides a process comprising the steps of
(a) contacting the oil or residue with phenol resin to provide a treated oil or residue
(b) separately to step (a), combining phenol resin and diluent to provide a diluted phenol resin
(c) combining the treated oil or residue and the diluted phenol resin to provide a diluted phenol resin treated oil or residue; and
(d) optionally removing solid material from the diluted phenol resin treated oil or residue.
In one preferred aspect then the oil or residue is contacted with the phenol resin (either alone or in combination with the diluent) it is heater and/or agitated.
As noted herein the removal of solid material from the diluted phenol resin treated oil or residue is optional. In a preferred aspect this removal is performed. Preferably the solid materials are removed by filtration.
In one preferred aspect when the oil or residue is contacted with the phenol resin (either alone or in combination with the diluent) the oil or residue is at a temperature of 60-100° C.
In one preferred aspect when the diluent is contacted with the oil or residue resin (either alone or in combination with the phenol resin) the diluent is at a temperature of 60-100° C.
In one preferred aspect the diluted oil or residue or the diluted phenol resin treated oil or residue is heated to a temperature of 80-110° C. for a period of 10 to 240 minutes.
In one preferred aspect the diluted oil or residue or the diluted phenol resin treated oil or residue is heated to a temperature of 80-110° C. for a period of 90 to 150 minutes.
In one preferred aspect the diluted phenol treated oil or residue is cooled prior to removal of solids.
Phenol Resin
In one aspect the phenol resin is a compound of Formula I
wherein m is at least 1; wherein n is at least 1; wherein the or each R1 is selected from alkyl groups, aromatic groups and heterocycles, and wherein ring A is optionally further substituted with groups selected from —OH, hydrocarbyl groups, oxyhydrocarbyl groups, —CN, —NO2, —SO3H, —SO2H, —COOH, —COOR4, —NH2, —NHR5, —SO2NH2, —SO2, —NHR6, CONH2, CONHR7, SH and halogens; wherein each of R4, R5. R6 and R7 is independently selected from hydrocarbyl groups.
In one preferred aspect m is greater than 1. In one preferred aspect, m is 1 to 50, such as 1 to 40, 5 to 30, or 10 to 20. In a preferred aspect, m is 11 to 15.
n may be any suitable integer. For example n may be from 1 to 10 such as 1 to 8, 1 to 5 or 1, 2 or 3. Preferably n is 1.
In one aspect the “linker” group may be branched. Thus in this aspect the phenol resin may be a compound of Formula Ia
wherein m is at least 1; wherein n is at least 1; wherein the or each R1 is selected from alkyl groups, aromatic groups and heterocycles, and wherein ring A is optionally further substituted with groups selected from —OH, hydrocarbyl groups, oxyhydrocarbyl groups, —CN, —NO2, —SO3H, —SO2H, —COOH, —COOR4, —NH2, —NHR5, —SO2NH2, —SO2, —NHR6, CONH2, CONHR7, SH and halogens; wherein each of R4, R5. R6 and R7 is independently selected from hydrocarbyl groups.
R1 may be a linear or branched alkyl group.
In one aspect, preferably R1 is a C1-C200 alkyl group, preferably a C1-C150 alkyl group, preferably a C10-C100 alkyl group, preferably a C1-C80 alkyl group, preferably a C1-C50 alkyl group, preferably a C1-C20 alkyl group, preferably a C5-C20 alkyl group, preferably a C5-C15 alkyl group, preferably a C6-C12 alkyl group, preferably a C7-C11 alkyl group, preferably a C8-C10 alkyl group, more preferably a C9 alkyl group.
In one aspect, R1 is a branched alkyl group, preferably a C3-6 branched alkyl group, for example t-butyl.
In one aspect, R1 is a straight chain alkyl group.
In one aspect, preferably R1 is a C1-C200 straight chain alkyl group, preferably a C1-C150 straight chain alkyl group, preferably a C10-C100 straight chain alkyl group, preferably a C1-C80 straight chain alkyl group, preferably a C1-C50 straight chain alkyl group, preferably a C1-C20 straight chain alkyl group, preferably a C5-C20 straight chain alkyl group, preferably a C5-C15 straight chain alkyl group, preferably a C6-C12 straight chain alkyl group, preferably a C7-C11 straight chain alkyl group, preferably a C8-C10 straight chain alkyl group, more preferably a C9 straight chain alkyl group.
In one preferred aspect R1 is para substituted relative to the OH group.
In one preferred aspect the (CH2)n group is ortho substituted relative to the OH group.
Preferably R1 is para substituted relative to the OH group and the (CH2)n group is ortho substituted relative to the OH group.
It will appreciated by one skilled in the art that the each of the “units” of Formula I may contain one or more further substituents. The “units” of Formula I independently of each other may be optionally substituted. As discussed herein ring A is optionally further substituted with groups selected from —OH, hydrocarbyl groups, oxyhydrocarbyl groups, —CN, —NO2, —SO3H, —SO2H, —COOH, —COOR4, —NH2, —NHR5, —SO2NH2, —SO2, —NHR6, CONH2, CONHR7, SH and halogens; wherein each of R4, R5. R6 and R7 is independently selected from hydrocarbyl groups. In a preferred aspect at least one of the “units” is unsubstituted. In a further preferred aspect each of the “units” is unsubstituted.
Thus, in one aspect, the compound of Formula I is a compound of Formula II
wherein the or each R2 is an optional group independently selected from —OH, hydrocarbyl groups, oxyhydrocarbyl groups, —CN, —NO2, —SO3H, —SO2H, —COOH, —COOR4, —NH2, —NHR5, —SO2NH2, —SO2, —NHR6, CONH2, CONHR7, SH and halogens; wherein each of R4, R5. R6 and R7 is independently selected from hydrocarbyl groups; and wherein m, n and R1 are as herein defined.
In a further aspect the compound is a compound of Formula IIa
wherein the or each R2 is an optional group independently selected from —OH, hydrocarbyl groups, oxyhydrocarbyl groups, —CN, —NO2, —SO3H, —SO2H, —COOH, —COOR4, —NH2, —NHR5, —SO2NH2, —SO2, —NHR6, CONH2, CONHR7, SH and halogens; wherein each of R4, R5. R6 and R7 is independently selected from hydrocarbyl groups; and wherein m, n and R1 are as herein defined.
Thus, in one aspect, the compound of Formula I is a compound of Formula III
wherein the or each R2 and R3 is an optional group independently selected from —OH, hydrocarbyl groups, oxyhydrocarbyl groups, —CN, —NO2, —SO3H, —SO2H, —COOH, —COOR4, —NH2, —NHR5, —SO2NH2, —SO2, —NHR6, CONH2, CONHR7, SH and halogens; wherein each of R4, R5. R6 and R7 is independently selected from hydrocarbyl groups; and wherein m, n and R1 are as herein defined.
In a further aspect the compound is a compound of Formula IIIa
wherein the or each R2 and R3 is an optional group independently selected from —OH, hydrocarbyl groups, oxyhydrocarbyl groups, —CN, —NO2, —SO3H, —SO2H, —COOH, —COOR4, —NH2, —NHR5, —SO2NH2, —SO2, —NHR6, CONH2, CONHR7, SH and halogens; wherein each of R4, R5. R6 and R7 is independently selected from hydrocarbyl groups; and wherein m, n and R1 are as herein defined.
In these aspects preferably R2 and/or R3 is an optional hydrocarbon group, more preferably an optional linear or branched alkyl group.
The term “hydrocarbon” as used herein means any one of an alkyl group, an alkenyl group, an alkenyl group, an acyl group, which groups may be linear, branched or cyclic, or an aryl group. The term hydrocarbon also includes those groups but wherein they have been optionally substituted. If the hydrocarbon is a branched structure having substituent(s) thereon, then the substitution may be on either the hydrocarbon backbone or on the branch; alternatively the substitutions may be on the hydrocarbon backbone and on the branch.
In this aspect, preferably R2 and/or R3 is an optional group independently selected from a C1-C50 group, preferably a C1-C40 group, preferably a C1-C30 group, preferably a C1-C25 group, preferably a C1-C15 group.
A typical example of R2 or R3 is a tertiary alkyl group, such as a tertiary butyl group.
In a preferred aspect each of R2 and R3 are present such that ring A is fully substituted.
Preferably wherein ring A is optionally further substituted with groups selected from —OH, hydrocarbyl groups, oxyhydrocarbyl groups, —CN, —NO2, —SO3H, —SO2H, —COOH, —COOR4, —NH2, —NHR5, —SO2NH2, —SO2, —NHR6, CONH2, CONHR7, SH and halogens; wherein each of R4, R5. R6 and R7 is independently selected from hydrocarbyl groups.
In a preferred aspect the phenol resin is a substituted phenol resin. More preferably the phenol resin is the reaction product of substituted phenol and an aldehyde.
More preferably the phenol resin is the reaction product of substituted phenol and an aldehyde having 1-7 carbon atoms, for example formaldehyde.
In a preferred aspect the phenol resin is a nonyl phenol resin. More preferably the phenol resin is the reaction product of nonyl phenol and formaldehyde, or of t-butyl phenol and an aldehyde having 1-7 carbon atoms, for example formaldehyde.
Alkoxylated phenol resins (ethoxylated and/or propoxylated) are available. Their use is not excluded, but it is not preferred, as excellent results have been obtained using non-alkoxylated phenol resins.
The phenol resin may be contacted with the oil or residue in any suitable amount. Preferably the phenol resin is contacted with the oil or residue in an amount of 2 to 10,000 ppm based on the amount of oil or residue, such as in an amount of 5 to 5,000 ppm based on the amount of oil or residue, such as in an amount of 10 to 2,000 ppm based on the amount of oil or residue, or in an amount of 50 to 400 ppm based on the amount of oil or residue, or in an amount 200 to 350 ppm based on the amount of oil or residue.
Diluent
The diluent may be any suitable diluent
Typically the diluent is a crude oil distillation product selected from kerosene, cracked gas oil, vacuum gas oil, long residue, short residue, heavy naptha, light gas oil, medium gas oil, heavy gas oil, cycle oil, gasoline, diesel and mixtures thereof.
Preferably the diluent is a vacuum gas oil. In one preferred aspect the diluent is a light vacuum gas oil. By the term “light vacuum gas oil” it is typically meant a gas oil fraction from a vacuum distillation tower, which will typically have a boiling range of 350-630° C.
Further Aspects
In a further aspect the present invention provides a treated crude oil or a treated aged crude oil residue prepared by a process as defined herein.
In a further aspect the present invention provides a treated crude oil or a treated aged crude oil residue obtainable by a process as defined herein.
In a further aspect a fuel (such as a residual fuel oil, boiler fuel or marine fuel) comprising treated crude oil or treated aged crude oil residue prepared by or obtainable a process as defined herein.
The fuel of the present invention (such as a residual fuel oil) typically has a density at 15° C. of no greater than 1010 kg/m3, for example 960 kg/m3.
The fuel of the present invention (such as a residual fuel oil) typically has a pour point of no greater than 30° C., for example −14° C.
The fuel of the present invention (such as a residual fuel oil) typically has a flash point of at least 60° C., for example 129° C.
The fuel of the present invention (such as a residual fuel oil) typically has a sulphur content of no greater than 5 wt % for marine bunkers, or no greater than 3.5 wt % for land use.
The fuel of the present invention (such as a residual fuel oil) typically has a water content of no greater than 1% vol, for example no greater than 0.1% vol.
The fuel of the present invention (such as a residual fuel oil) typically has a viscosity at 100° C. of 5 to 50 mm2/s, for example a viscosity at 50° C. of 42 mm2/s.
The present invention further provides use of a phenol resin for increasing the stability of a crude oil or an aged crude oil residue.
The present invention further provides use of a phenol resin for increasing the stability of asphaltenes in a crude oil or an aged crude oil residue.
The present invention will now be described in further detail in the following examples.